Water cooler and hot water accessory kit therefor



Dec. 7, 1965 R. J. BIRMINGHAM 3,221,306

WATER COOLER AND HOT WATER ACCESSORY KIT THEREFQR Filed 001;- 5, 1962 United States Patent 3,221,806 WATER COOLER AND HOT WATER ACCESSORY KIT THEREFOR Roy J. Birmingham, Homewood, IlL, assignor to General Electric Company, a corporation of New York Filed Oct. 3, 1962, Ser. No. 228,141 11 Claims. (Cl. 165-64) This invention relates to electric water coolers, and more particularly to an electric hot water accessory kit which may be added to an existing cooler so that it may provide both hot and cold water.

Electric water coolers to provide refrigerated drinking water in offices and public places offer increased utility if provision is also made to dispense hot water. The device then becomes a refreshment center, with cold drinking water when desired, and also hot water for making instant beverages and the like. While such hot and cold water dispensers have heretofore been made and sold, it has thus far been required by electrical safety codes and regulations that the water heater components and the electrical refrigeration components be pro-wired at the factory, and with electrical power supply for the entire appliance supplied through a single electrical cord and plug which includes a ground connection. While the ground connection is intended to ground the entire device, it is found in practice that on occasion this connection to electrical ground may be defective or partially in operative. In this case, the appliance can deliver a shock to the user. This risk is doubled if the electrical components for the refrigeration system are plugged into a power outlet separately from the electrical water heater.

correspondingly, it has been deemed poor engineering and safety practice to add a hot water heater to an existing Water cooler, with installation by the customer or user,

. since this would entail power supply to the water heater through a separate electrical plug, giving rise to a double shock hazard. For this reason, electrical codes and regulations have heretofore made it inadvisable to make and sell hot water heaters suitable for addition to existing water coolers. However, many owners of water coolers desire to add a hot water supply as a convenience. This is especially desirable in offices where ready availability of hot water to the employees can save the time lost in leaving the oifice premises for refreshments.

An object of the present invention is to provide a hot water accessory kit for addition to existing water coolers, with an essentially fool-proof electrical arrangement to obviate the double shock hazard.

Another object of this invention is to provide such a hot water accessory kit which can be readily installed in 7 an existing electric water cooler by the user, without engaging expert help, and without the necessity of inspections to insure compliance with electrical codes and regulations.

In accordance with one aspect of the present invention,

' I provide a hot water accessory kit in the form of a complete enclosure, from which extends an electrical power .supply cord of the type adapted to. be plugged into a con- Ventional electrical outlet. The exterior of this enclosure "also presents the insulated face of an electrical power outlet receptacle to receive the plug on the end of the electric service cord for the electric water cooler. All of because this switch is open. The switch can only be closed 3,221,806 Patented Dec. 7, 1965 ICC by plugging in the power or service cord for the Water cooler into the receptacle on the water heater enclosure. Correspondingly, when the installation has been completed, there is only a single power supply cord extending from the appliance to a power outlet in the wall, this power supply cord providing electrical energy for both the refrigeration system and for the electric heater of the hot water unit.

Further objects and advantages of the present invention will be better understood by reference to the following description, taken in connection with the accompanying drawing, in which:

FIG. 1 is a perspective View of a water cooler embodying a hot water heater in accordance with this invention, with surfaces being partially broken away to illustrate details;

FIG. 2 is a plan view of the interior of the electrical receptacle used in the practice of this invention;

FIG. 3 is a sectional elevation through the electrical receptacle, taken on the line 3-3 of FIG. 2; and

FIG. 4 is a schematic electrical wiring diagram.

Referring now to the drawing, I have illustrated my invention as embodied in an electric water cooler of the type found frequently in public places and ofiices. Typically, the operating components are enclosed within a cabinet 1, mounted on a supporting base 2. In the usual manner, a water fountain basin 3 of stainless metal or porcelain enamel is mounted on the cabinet to receive any excess water which may issue from the water fountain 4, and direct it to a suitable drain (not shown). The fountain may be turned on at will by an operator by depressing the bar 5, or a suitable foot operated pedal, in a well-known manner.

It is intended that the water cooler be connected to a supply of water, for example at the connection pipe 6 located at the back of the cabinet. Pipe 6 extends within the cabinet to a water chilling tank 7, with the cooling coils 8 of a refrigeration system in thermal contact with the water chilling tank, thereby to cool the Water in the tank to the desired drinking temperature. The water chilling tank is suitably connected by a pipe or tube 9 to the bubbler or fountain head 4.

An electrically powered refrigeration system is mounted within cabinet 1, and as here shown somewhat schematically, includes a sealed motor-compressor unit '10 in the lower part of the cabinet. Compressor unit 10 discharges compressed refrigerant into a condenser coil 11 over which cooling air is circulated by a fan (not shown) driven by a fan motor 12. The cooled refrigerant then passes through a suitable expansion valve or capillary tube to the evaporator or cooling coil 8 of the refrigeration systern, and from the evaporator coil, the refrigerant gas is returned to the suction side of the compressor unit '10. The details of the refrigeration system do not form'a part of the present invention, and it is to be understood that any suitable electrically powered refrigeration system may be used for chilling or cooling water tank 7.

For operation, the electric motor-compressor unit. 10 must, of course, be supplied. with electric power; andfor this purpose, the water cooler is normally provided with an electric power or service cord 13, on the end of which is a conventional power plug 14. As shownmore clearly in FIG. 4, the; power plug for an appliance of thisty-pe includes two blades 15 and 16 to engage thepower clips in a conventional wall receptacle; and in addition, a ground pin 17 is provided as ameans to conveniently ground the entire device. The insulated service cord 13 (FIG. 1) actually includes three mutually insulated electrical conductors 18, 19, and 20 (FIG. 4). As shown, conductors 18 and 19 supply operating electrical power to the motor-compressor unit, while conductor 20 provides the ground connection from ground pin 17 on the plug to a suitable grounding connection within the cabinet. While conductor 20 is shown as connected to motor-compressor in FIG. 4, it will be understood that any suitable connection may be made which will effectively ground not only the outer metal case of the motor-compressor unit, but also the entire cabinet and frame of the water cooler.

For the purposes of describing this invention, let it be assumed that the customer has the water cooler, as above described, in location, connected both to the cold water supply and to the electrical power supply. The users are, of course, supplied with cold drinking water from the bubbler or fountain head 4. It is now desired to add to this appliance means for supplying hot drinking water, useful for making instant beverages, soups, and the like. The present invention is directed to a hot water accessory kit which can readily be added to the water cooler with a minimum of installation expense, and without providing a double electrical shock hazard, which would exist if the water cooler and the electric heater were separately connected to electrical outlet receptacles.

Referring again to FIG. 1, the electric hot water accessory is manufactured and sold as a completely enclosed unit, with all of the components within an enclosure 21, from which extends a three-conductor electric power cord 22, on the end of which is a three-prong power plug of the type previously described, thus providing two power supply conductors to the device along with an electrical ground conductor. Within enclosure 21 is a hot water tank 23, and mounted therein is an electric immersion heater 24, having electric terminals 25 and 26. A temperature responsive thermostatic switch 27 is mounted on the tank to control operation of the heater 24 and thereby maintain the water in the tank at the desired temperature, for example 180 F. The hot water tank also includes, of course, a water pipe 28 for connection into the water supply pipe 6, and thus a common water supply line supplies water to both the water cooler and the water heater. At the upper end of the hot water tank is an outlet connection, from which extends an appropriate discharge tube 30. A handle 31 is shown for operating a control valve (not shown), preferably located in the incoming supply line 28, so that a pressure relief valve on the tank becomes unnecessary.

Also mounted in enclosure 21 is a combined power outlet receptacle and switch unit 32, adapted to receive the three-prong power plug for the electric service cord leading to motor-compressor unit 10, as shown in FIG. 1. The details of this combined outlet receptacle and switch unit are shown in FIGS. 2 and 3, to which reference is now made.

The housing 33 for receptacle 32 is of electrical insulating material, such as molded phenolic. Appropriate recesses are molded within the housing to receive four metallic electrical conductors, which are then held in fixed position within the housing by an enclosing plate 34 of insulating material. One of these metallic electrical conductors is in the form of a one-piece clip 35 to which is secured an incoming electrical power lead 36. Clip 35 also includes a pair of spring arms 37 to receive and make electrical connection with the blade of a connection plug, such as blade 16, as shown in FIG. 4. Clip 35 also includes as an integral part thereof a connection terminal 38, as shown clearly in FIG. 3.

The other clip within receptacle 32 is a two-piece member with the two parts electrically insulated from one another. As shown by FIGS. 2 and 3, one of the clip parts 39 has an incoming electrical power lead 40 secured thereto, while the other clip part 41 includes integrally therewith a connection terminal 42. Clip parts 39 and 41 are supported within housing 33, so that they are insulated from one another; although the air gap between the ends of the clip is sufficiently small to be bridged by the insertion of the blade, such as 15, of a connection plug. In other words, when a plug is inserted into receptacle 32, an electrical circuit is completed from conductor 40 to terminal 42. While this particular manner of completing a circuit is preferred for simplicity, it will be apparent that a switch of another conventional form might also be used.

Provision is also made in receptacle 32 for an electrical ground connection. As shown in FIG. 2, the ground con nection is accomplished through a spring member 43 mounted within the insulating housing 33. A terminal screw 44 may provide a convenient means for attachment of a ground lead. In a manner well known in the art, spring member 43 is positioned within the receptacle to be engaged by a ground pin, such as 17 (FIG. 4) of an electrical connection plug.

While illustration of the electrical wiring has been omitted from FIG. 1, the details of the manner in which the various components are interconnected is clearly shown in FIG. 4. The three-conductor electrical connection or service cord 22 for the hot water accessory kit includes a service plug 45, provided with two blades 46 and 47 and a ground pin 48 for engagement with a wall or floor electrical outlet receptacle. The blades 46 and 47 are connected through two of the three electrical conductors in the service cord 22 with the leads 36 and 40 leading into the electrical receptacle 32, the connections being made in any suitable manner, such as by wire nuts 49 and 50. Lead 36, in turn, is connected to clip 35 within the receptacle, from which an electrical power connection is made by conductor 53 to one terminal 26 of heater 24. From the other terminal 25 of the heater, a lead 52 provides the connection to a terminal of thermostat 27. The other terminal of the thermostat is then connected by a lead 51 to terminal 42 of clip part 41. At this point, it may be noted that there normally is no electrical connection from clip part 41 to clip part 39, and hence heater 24 is not energized, even though the thermostatic switch 27 may be closed and the plug is inserted into an electric power outlet receptacle. In other words, blade parts 39 and 41 act as a normally open switch. As clearly shown in FIG. 4, the other clip part 39 returns to the other side of the power line through conductor 40.

From the foregoing description, the operation of this arrangement will be readily apparent. The water cooler may be operated in a normal manner by plugging in its service cord 13 to a suitable power receptacle. Assuming that water connection has been made, cooled water will be available for drinking whenever operating member 5 is depressed.

If hot water is also desired for the appliance, it is merely necessary to install the completely assembled hot water unit 21. Unit 21 has exposed plumbing connections for the incoming water line and for the discharge member 30. However, it will be noted that the hot water unit is not electrically energized, even though its power service cord is connected to a power outlet. As previously explained, the circuit is open at receptacle spring contact arms 39 and 41. Thus, the user must disconnect the water cooler service cord from its power outlet by unplugging it, following which the water cooler service plug 14 is inserted into power outlet receptacle 32 of the hot Water accessory unit. Thereupon, electrical power and ground connections are provided, and both the water heater and the water cooler are operative. The user is protected from the hazard that either one or the other of the electrical systems might have or develop, through a failure, an internal electrical short circuit.

While the above invention has been described by reference to a specific embodiment thereof, it will be under stood that all equivalent modifications and variations within the spirit of the invention are included within the scope of the following claims.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. A hot water accessory unit for an electric water cooler having a power supply plug comprising: a hot water tank; an electric Water heater for said tank; an outlet receptacle to receive the power supply plug of the water cooler; normally open switch means; an enclosure surrounding said tank, heater, switch means and receptacle with only the plug receiving face of said receptacle exposed; a power supply cord leading into said enclosure; connection means within said enclosure to supply power from said cord to said receptacle and to said electric heater in a series circuit including said switch means; and means closing said switch means when the water cooler plug is engaged with said receptacle to thereby supply power to said heater when said cord is connected to a power source.

2. The combination of claim 1, in which said switch means is defined by a two piece metallic clip in said receptacle, said two pieces being electn'callyinsulated and spaced to receive a blade of the water cooler power plug andthereby complete the circuit through said two piece metallic clip.

therefor; an electrical power cord entering said enclosure;

a power outlet receptacle mounted in said enclosure with an exposed face to receive the power plug of the water cooler; connection means within said enclosure to supply power from said cord to said receptacle; normally open switch means within said receptacle; means actuating said switch means to closed position upon insertion of the power plug of the water cooler into said receptacle; and means connecting said electric heater in electrical series with said switch means.

4. The combination of claim 3 in which said normally open switch is defined by a two piece metallic clip in said receptacle, with the two pieces insulated from one another, an electrical power connection to one of said two pieces, and a connection from the other of said two pieces to said electric water heater; said two piece metallic clip having portions thereof closely spaced so that an electric circuit therethrough is completed by insertion of a power plug into said receptacle.

5. An electric water heater accessory appliance for addition to an electric drinking fountain having a three blade power plug comprising: a hot water tank including connecting means to a water line and a manually operated valve for controlling discharge therefrom; an electric heater for said tank with a pair of terminals therfor; a power supply cord having two electric power conductors and .a ground conductor; a receptacle of insulating material having mounted therein a one piece metallic clip, a two piece metallic clip with the two pieces thereof insulated from one another, and a ground connection and clip, said clips forming the electrical contacts of said receptacle to receive the three blade plug for the electric drinking fountain, electrical connection through the two piece clip being completed when said plug is inserted; electrical connections from said power cord to said clips and from said one piece and two piece clips to the terminals of said heater, the circuit to said heater remaining open through said two piece clip until the water fountain power plug is inserted into said receptacle; and an enclosure for said water tank and the electrical connections therefor with only the insulated face of said receptacle exposed and positioned to receive the water fountain power plug.

6. An electric water heater accessory appliance for addition to an electric water cooler having a three blade power plug comprising: a hot water tank; an electric heater for said tank with a pair of terminals therefor; a power supply cord having two electric power conductors and a ground conductor; an electric receptacle having three contacts therein consisting of two power contacts and a ground contact to receive the three-blade power plug for the water cooler, means connecting said two 6 power conductors to said power contacts and connecting said ground conductor to said ground contact; means defining a normally open single pole switch in said receptacle having one terminal thereof connected to one power contact and the other terminal connected to a water heater terminal; means connecting the other terminal of said heater to the other power contact; and means closing said switch upon insertion of the water cooler power plug into said receptacle.

7. An electric water heater accessory appliance for addition to an electric drinking fountain having a three blade power plug comprising: a hot water tank including connecting means to a water line and a manually operated valve for controlling discharge therefrom; an electric heater for said tank with a pair of terminals therefor; a power supply cord having two electric power conductors and a ground conductor; a combined power outlet receptacle and switch having three electric contacts and a ground contact therein respectively insulated from one another; means connecting two of said contacts respectively to said two electric power conductors and said ground conductor to said ground contact; means connecting said electric heater terminals respectively to the third electric contact and to one of said two contacts; the contacts connected to said electric power conductors and said ground contact defining the electric circuit elements of said power outlet receptacle to receive the three-blade power plug for the electric water cooler; and means positioning the third electric contact in said receptacle in proximity to the other of said two contacts to define said switch, whereby insertion of the power plug for the electric water cooler into said receptacle both supplies power for the water cooler and closes the switch to complete the electric power circuit through said third electric contact to said electric heater.

8. An electric drinking water appliance comprising: an electrically powered refrigeration system including a cooling evaporator; an electric power cord for said refrigeration system and a plug therefor for connection to a standard power outlet receptacle with at least one ground wire; a cold water system connected to a water supply, cooled by said evaporator and discharging at a drinking fountain outlet; a separate electric water heater adapted to be combined with or removed from said drinking water appliance, said water heater including a water tank, a water connection to the water supply, an electric heater for said water tank, and a valved outlet from said water tank to discharge hot water; a main power cord having two power conductors and a ground conductor and adapted for connection to a power source, a grounding power receptacle including a grounding clip connected to said ground conductor, a first one piece metal clip connected to one of said power conductors and to one terminal of said electric heater, a second two piece metal clip with one piece thereof connected to the other power conductor and with the other piece thereof connected to the other terminal of said electric heater, said two pieces of the second clip being electrically insulated from one another with portions thereof closely spaced, said first and second clips forming the electrical contacts. of the power receptacle whereby insertion of the plug for said refrigeration system into said receptacle completes the electrical connection to said electric heater by interconnecting the two pieces of said second clip.

9. An electric water dispensing appliance comprising: an electric water cooler; an electrical plug for said water cooler; a separate electric water heater adapted to be combined with and removed from said cooler, said water heater including an enclosure; an electric heating element within said enclosure; an outlet receptable within said enclosure formed of insulating material and adapted to receive the plug of the water cooler; said receptacle including normally open switch means and having an exposed plug-receiving face; a main power supply cord leading into said enclosure; means within said enclosure connecting said cord to said receptacle to supply power to said water cooler when the plug for the water cooler is received in said receptacle and when said cord is connected to a source of power, said last-named means also connecting said cord to said electric heating element through said switch means; and means closing said switch means when the water cooler plug is engaged with said receptacle to thereby supply power to said heating element when said cord is connected to a source of power.

10. An electric appliance assembly comprising: a first electric appliance; an electrical plug for said first appliance; a separate second electrical appliance adapted to be combined with and removed from said first appliance; said second appliance including an enclosure; an electroresponsive element adapted for energization within said enclosure; an outlet receptacle within said enclosure formed of insulating material and adapted to receive the plug for the first appliance; said receptacle including normally open switch means and having an exposed plugreceiving face; a main power supply cord leading into said enclosure; means within said enclosure connecting said cord to said receptacle to supply power to said first appliance when the plug for said first appliance is received in said receptacle and when said cord is connected to a source of power, said last-named means also connecting said cord to said electroresponsive element through said switch means; and means closing said switch means when the plug for said first appliance is engaged with said receptacle to thereby supply power to said electroresponsive element when said cord is connected to a source of power.

11. An accessary electrical appliance unit for association with a first appliance having an electrical plug comprising: an enclosure; an electroresponsive element adapted for energization within said enclosure; an outlet receptacle within said enclosure having a plug-receiving face exposed to receive the plug of the first appliance; normally open switch means within said enclosure; a power supply cord leading into said enclosure; electrical connections Within said enclosure to supply power from said cord to said receptacle, and to said electroresponsive element through said switch means; and means closing said switch means in response to insertion of said plug into said receptacle to thereby supply power to said electroresponsive element when said cord is connected to a source of power.

References Cited by the Examiner UNITED STATES PATENTS 2,784,879 3/1957 Fischer 165-64 FREDERICK L. MATTESON, ]R., Primary Examiner.

CHARLES SUKALO, Assistant Examiner. 

8. AN ELECTRIC DRINKING WATER APPLIANCE COMPRISING: AN ELECTRICALLY POWERED REFRIGERATION SYSTEM INCLUDING A COOLING EVAPORATOR; AN ELECTRIC POWER CORD FOR SAID REFRIGERATION SYSTEM AND A PLUG THEREFOR, FOR CONNECTION TO A STANDARD POWER OUTLET RECEPTACLE WITH AT LEAST ONE GROUND WIRE; A COLD WATER SYSTEM CONNECTED TO A WATER SUPPLY, COOLED BY SAID EVAPORATOR AND DISCHARGING AT A DRINKING FOUNTAIN OUTLET; A SEPARATE ELECTRIC WATER HEATER ADAPTED TO BE COMBINED WITH OR REMOVED FROM SAID DRINKING WATER APPLIANCE, SAID WATER HEATER INCLUDING A WATER TANK, A WATER CONNECTION TO THE WATER SUPPLY, AN ELECTRIC HEATER FOR SAID WATER TANK, AND A VALVED OUTLET FROM SAID WATER TANK TO DISCHARGE HOT WATER; A MAIN POWER CORD HAVING TWO POWER CONDUCTORS AND A GROUND CONDUCTOR AND ADAPTED FOR CONNECTION TO A POWER SOURCE, A GROUNDING POWER RECEPTACLE INCLUDING A GROUNDING CLIP CONNECTED TO SAID GROUND CONDUCTOR, A FIRST ONE PIECE METAL CLIP CONNECTED TO ONE OF SAID POWER CONDUCTORS AND TO ONE TERMINAL OF SAID ELECTRIC HEATER, A SECOND TWO PIECE METAL CLIP WITH ONE PIECE THEREOF CONNECTED TO THE OTHER POWER CONDUCTOR AND WITH THE OTHER PIECE THEREOF CONNECTED TO THE OTHER TERMINAL OF SAID ELECTRIC HEATER, SAID TWO PIECES OF THE SECOND CLIP BEING ELECTRICALY INSULATED FROM ONE ANOTHER WITH PORTIONS THEREOF CLOSELY SPACED, SAID FIRST AND SECOND CLIPS FORMING THE ELECTRICAL CONTACTS OF THE POWER RECEPTACLE WHEREBY INSERTION OF THE PLUG FOR SAID REFRIGERATION SYSTEM INTO SAID RECEPTACLE COMPLETES THE ELECTRICAL CONNECTION TO SAID ELECTRICAL HEATER BY INTERCONNECTING THE TWO PIECES OF SAID SECOND CLIP. 